VX-4 phantom loads

On Thu, 10 Mar 2005 22:52:45 GMT, Guy Alcala
wrote:

Ed Rasimus wrote:

On 9 Mar 2005 08:33:25 -0800, "Bob" wrote:

The Navy did not use wing tanks on their F-4's. The normal external
tank configuration was the single centerline tank. The reason was that
wing tanks made the already cumbersome F-4 even harder to turn. Roll
rate was reduced and nose high maneuvers were harder.

The Navy bought a different centerline tank than USAF did. (Not sure,
but as I recall it was a MacAir tank for USN and a Sargent-Fletcher
for AF).

From an RF-4C stores limitation chart, the USAF used McAir and Royal Jet C/L
tanks. McAir and Sargent-Fletcher made the wing tanks. The McAir C/L
limits are somewhat higher than the Royal Jet's, but the jettison limits are
the same.

You are correct--it was the Royal Jet tank, not Sargent-Fletcher. But,
the flight load limits for the RJ tank are a lot lower than the McAir.

As far as jettison limits (which hadn't been addressed until this
point), let me suggest that anyone who was jettisoning the RJ tank at
the published flight conditions was looking for a belly bumping
experience. The 'rule-of-thumb' we used with good results was one G
for every 100 knots of airspeed at jettison. Going 400 KIAS? Then pull
to 4 G before hitting the button. Clean separation guaranteed.

I'll confess to only having done it about 100 times, so others may
have different experiences.

The Navy tank was stressed for close to aircraft limits and
with lower drag than a pair of outboard 370s made for better
efficiency all around.

Drag appears to be the same as a pair of 370s.

Drag index of 12.8 for two 370s. Drag of 9.6 for one C/L 600.

snip

Normally each
F-4 carried 2 Aim-7 missiles in the under fuselage cavities and four
Aim-9H or G missiles on under wing pylons.

Here you highlight one shortcoming of the C/L tank option. Two of the
four missile wells couldn't be used.

Considering the reliability of AIM-7s after a few cat shots and traps, I
imagine it wasn't a big deal. And you could always punch the tank. By 1972
USAFf-4s were normally just carrying a pair of AIM-7s in the aft wells, with
jamming or camera pods in the forward wells.

By 1972, I was just checking out in the F-4 and arriving in theater.
We were NORMALLY carrying three AIM-7s on all missions with one pod in
a forward missile well. No camera pods.

A M-60 gun pod (SU-23) was tested. This pod was about
the size of a centerline fuel tank, fired 20mm bullets and was mainly
tested to get some gun data on the M-60 which was then used exclusively
by the USAF.

Both SUU-23 and SUU-19 were carried by USAF F-4C and D models. Only
major difference was that the -19 was RAT driven while the 23 was
electrically spun. Good guns that could be very effective against
ground targets.

Ed, you meant SUU-16, not -19.

You are correct. SUU-16.


Ed Rasimus
Fighter Pilot (USAF-Ret)
"When Thunder Rolled"
www.thunderchief.org
www.thundertales.blogspot.com